1. Field
Provided are microfluidic devices having a microvalve, and more particularly, microfluidic devices including microstructures on a surface of an elastic film in a microvalve.
2. Description of the Related Art
An analysis of samples related to clinics or the environment is achieved through a biochemical, chemical, or mechanical treatment process. Recently, the development of techniques for diagnosing or monitoring a biological sample has drawn a significant interest. The application of a molecular diagnosis method based on nucleic acid has significantly increased recently in the fields of diagnosing an infectious disease or cancer, pharmacogenomics, or developing a new medicine due to its high accuracy and sensitivity. A microfluidic device is widely used for simply and precisely analyzing a sample according to various purposes. The microfluidic device includes a plurality of sample inlets, sample outlets, microfluidic channels, and reaction chambers, and thus, simply performs various tests on a single sample. Accordingly, the microfluidic device uses various kinds of sensors and platforms for amplifying/diagnosing a bio-sample, and developing a new medicine.
The microfluidic device may further include fine microvalves and micropumps so that a sample and a reagent may be correctly supplied to target positions in the microfluidic device. A microvalve is disposed in a microfluidic channel in the microfluidic device. The microvalve may be formed by disposing an elastic film and a valve seat in the microfluidic channel of the microfluidic device. In such a microvalve structure, generally, the microvalve is closed while the elastic film contacts the valve seat, and accordingly, a sample may not pass the microfluidic channel. Conversely, while the elastic film is separated from the valve seat, the microvalve is opened, and thus, a sample may pass the microfluidic channel.
However, in the case of a conventional microvalve, normally, the elastic film and the valve seat contact each other when the microvalve is not in operation. Thus, after a lapse of time, the elastic film may stick to the valve seat. In this case, the opening and closing operations of the microvalve may not be smoothly performed when the microvalve is finally operated. In order to prevent stiction or sticking between the elastic film and the valve sheet when the microvalve is finally operated, the manufacturing process of the microfluidic device may be complicated.